Means for starting internal-combustion engines



May 15, 1928.

H. R. RICARDO MEANS FOR STARTING INTERNAL COMBUSTION ENGINES 2 Sheets- Sheet 1 Filed March 29. 1926 J3 5 Jfa B May 15, 1928. 1,669,780

- H. R. RICARDO MEANS FOR STARTING INTERNAL COMBUSTION ENGINES Filed March 29. 1926 2 Sheets-Sheet 2 j'wrewfar Patented May 15, 1928.

UNITED STATES HARRY B ALPH RICARDO, OF LONDON, ENGLAND.

MEANSIOR s'raarme m'rnana n-comnosrxon mamas.

Application filed March 29, 1926, Serial No.

This invention relates to sleeve valve internal combustion engines, more particularly those of the Diesel. and other high compression types, and has for its object to facilitate thestarting of such engines.

When starting high Compression internal combustion engines such as Diesel engines, by mechanically rotating them without the use of compressed air, difficulty is experienced in turning the engine over the first few compression strokes since the flywheel has not then acquired 'sufiicient. momentum to even up appreciably thetorque demandon the starting mechanism. If, however, a decompressor or some equivalent device is provided, this difficulty does not arise to such an extent and the engine can moreeasily be rotated until it reaches a speed at which the flywheel momentum is sufficient to overcome the compression resistance when the decompressor or equivalent device is cut out.

In poppet valve engines this decompression is easily eflected b lifting and thus holding open either the lnlet'or the exhaust valve until the engine has gained sufficient.

. speed but,v in a sleeve'valve engine, this is clearly impossible While the construction is generally such as to render undesirable the use of a special decompression valve.

According to one featureof the present invention means are provided for controlling the mechanism by which the sleeve valve is operated soas to enable the timing of such valve to be varied in relation to the crank shaft whereby the bharge compressed within the cylinder on each compression stroke can be reduced when starting the engine. In this manner both the quantit of the charge actually compressed and t e maximum compression pressure can be reduced to-an extent sufficientto make the starting of the engine by mechanical rotation relatively easy.

Thetiming of the valve or valves may be ,w altered that the inlet port or ports are closed early in the suction stroke thus reducing the charge drawn into the cylinder. With such an arrangement, however, acylinder in which the piston is initially at bottom dead centre will have acquired a full charge by leakage and it is preferable, there fore, in most cases to vary the valve timing so as to maintain the inlet port or ports open during a portion of the compression stroke vis conveniently 98,856, and in Great Britain' April 7, 1925.

so i that a substantial part of the char e drawn into the cylinder on the suction stro e is expelled again and the maximum compression thus reduced.

The variation in the valve timingin order to reduce the maximum compression pressure effected by altering the. phase relationship etween the sleeve valve or valves and the crank shaft in some suitable manner. For example, where each sleeve has motionimparted thereto both about and in the direction of its axis by means of a crank pin carried by a short shaft, this short shaft, which for the purposes of this specification will be termed the valve-operating crank shaft, may be driven from a lay shaft through skew or worm gearing the lay shaft in turn being driven by suitable gearing from the engine crank shaft. The alteration in the timing of the sleeve or sleeves in relation to the engine crank shaftis effected by moving the lay shaft or the skew or worm gears thereon longitudinally so as to rotate the valve-operating crank shafts independently of any rotation which ma be imparted thereto by the rotation o the lay shaft. v I Where the invention is applied to a multicylinder internal combustion engine, separate controlling means may be provided for varying the timing of the sleeve or sleeves of each cylinder or common control mechanism may be provided to vary the valve timing of all the cylinders simultaneously. Thus in the arrangement described above, a single-longitudinally movable lay shaft may convenientlydrive all the valve-operating 'crank shafts through skew or worm gearing.

In an alternative arrangement wherein each'sleeve is operated by a lever which serves to transmit motion from an eccentric or crank on a lay shaft to the sleeve through a spherical joint or other flexible connection, means may be provided for alterin the phase relationship between the lay sha t and as to cause relative rotation between theseskew gears independently of any rotation due to the rotation of the crank shaft, thus altering the base relationship between the lay shaft an the crank shaft. One of the skew ears for effecting this change in phase is ma e of sufiicient length to ensure proper engagement of the two gears throughout their relative movement.

The invention is particularly applicable to high compression liquid injection engines, such as Diesel engines, and according to a further feature of the present invention an interlocked or interconnection is preferably provided between the mechanism for varyirfiig the. valve timing and that for cutting o the liquid fuel supply this interconnection eing arranged so that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression. In this way the risk of liquid fuel accumulating in the cylinder while the engine is running on reduced compression and subsequently exploding when the valve gear is moved to its full compression position is avoided and the operation of starting is simplified since the movement of the valve gear to its full compression position and the admission of the liquid fuel to the cylinders can both be carried out by a single control lever.

In certain cases, for example for the purpose of warming up a compression ignition engine such as a Diesel engine, according to a further feature of the present invention it may be desirable when starting to supply such engine with a gaseous combustible mixture and to retain and compress a part thereof in the cylinder, running the engine as a low compression engine with electric or similar ignition until the engine has attained the desired speed. To t is end when starting a charge of combustible mixture may be supplied to the engine either through the main inlet port or ports or through'one or more auxiliary ports the supply of this charge being cut 0 when the valve timing is altered to the normal running or high compression position. Preferably the means for cutting off the fuel supply and those for altering the valve timing are interconnected or interlocked so as to eliminate any risk of raising a gaseous combustible charge to the high normalrunning compression of the engine since this might result in a dangerous preignition. The engine may be started as a low com ression engine either by hand or by some (nown means such as an electric starting motor.

In an engine according to this invention the control of the valve timing may be effected either by hand or automatically and where the operation is automatic, as for example by means of some form of governor, this is conveniently adapted to move the valve gear control from the starting to the running position either when the ing purposes or not.

engine has attained a predetermined speed or when the electric or other starting engine is cut out.

Where the invention is applied to direct reversin'g engines, the present means for varying the valve timing in order to reduce the compression pressure may be combined with the previously proposed means for varying the valve timing in order to effect the reversal of the engine so that a single control mechanism will give starting and running valve timin s both for forward and reverse running of t e engine.

Further, where an electric motor or other source of power is employed to start the engine, the starting switch or other member for bringing such starting motor into operation may according to this invention be interconnected or interlocked with the mechanism for varying the valve timing, whether such mechanism is'itself interconnected with means for controlling the liquid fuel supply to the cylinder or cylinders or the admission of a gaseouscharge for start- This interconnection is conveniently such that the starting motor I is thrown out of operation automatically when the valve gear control is moved to its normal running position while the starting motor cannot be put into operation while the valve gear control is in its normal running or high compression position.

The invention may be carried out in various ways but two alternative constructions according to this invention are illustrated by way of example in the accompanying drawings, in which:

Figure 1 is a side elevation partially in section of a multi-cylinder sleeve valve engine according to this invention in which each sleeve is operated by a separate crank shaft driven through skew gearing from a common lay shaft,

Fi re 2 is a diagrammatic plan view showing how the invention may be applied to a sleeve valve engine in which all the sleeves are driven through suitably arranged levers from a common lay shaft; and

Figure 3 is a section taken substantially on the line 3-3 of Fig. 1.

In the construction illustrated in Figure 1 the engine comprises a crank case A containing a crank shaft A and having mounted thereon cylinders 13 provided with fuel injection nozzles B. Inlet and exhaust ports B are provided in the wall of each cylinder and these ports are controlled in known manner by sleeve valves B having motion imparted thereto both about and in the direction of their axes. Each sleeve valve is adapted to be operated by a separate shaft C disposed with its axis at right angles to the axis of the cylinder and carrying for example a crank pin C which engages a spherical or other self aligning bearing C in the sleeve; Each of the.valve-operating shafts C has a skew gear or worm wheel C rigidly mounted thereon and engaging respectively a second skew gear or a worm D rigidly mounted on a lay shaft D which is conveniently disposed parallel with the crank shaft A of the engine and is common to all the sleeve valves. Y

The lay shaft D is supported at one end in a bearing 1*) and at the other end by a gear wheel F mounted in bearings F and 'is capable of sliding through the gear wheel F but is held from rotation relatively thereto, for example by splines or the like. The lay shaft is adapted to bedriven from the crank shaft-A by gearingcomprising for example a gear wheel G on the crank shaft engaging an intermediate gear wheel Gr meshing in turn with the gear wheel F and is adapted "to be moved longitudinally carrying the skew gears or worms D with it so as to rotate the valve-operating crank shafts C independently of the rotation imparted thereto by the rotation of the'lay shaft D, the skew gears or worms D on the lay shaft being of sufficient width to engage with their respect1ve cooperating skew gears or worm wheels C on the valve-operating shafts C throughout the longitudinal movement of the lay shaft D. The longitudinal movement of the lay-shaftD is conveniently effected by means of a hand lever H operating on a thrust bearing H on the lay shaft. This lever H may also control a valve through I which either a gaseous combustible charge from a carburettor or pure air from the at mosphere can be admitted to the induction pipe of'the engine according as the control lever is in its starting or its norn al running position respectively. y

'In the arrangement diagrammatically illustrated in Figure 1 this valve comprises a piston J adapted to'move in a cylinder J communicating with the induction pipe or manifold J of the engine. The upper end J 3 of the cylinder J is closed and communicates with a petrol or like carburettor J 4 while the lower end is open-tothe atmosphere. The piston is adapted to be operated by a link J 5 connecting it to the lever H and the arrangement is such that when this lever is in the starting position-so that the en ine is operating on low compression, the induction pipe J is placed in communication with the carburettor J 4 while when the lever H is in the normal running or full compression position the induction pipe is placed 111 communication w1th the atmosphere.

In this way the engine can if desired be started as a low compression engine running on the gaseous combustible charge from the carburettor, this charge being ignited by a sparking plug J or similar means while, when the control lever H is moved from its starting to its normal, running position, the gaseous combust ble charge 15 automatically cut off and pure-air 1s dehvered to the englne.

The control lever H may'also operate for example through a link K a by-pass or other control K acting on the fuel pumps indicated at L or on the supply of liquid fuel to the cylinders so that the liquid fuel injection is automatically cut off when the control lever H is in the starting position, while a switch may also be actuated by the lever H to cut off the ignition current when running with high compression on liquid fuel. Further a switch H controlling an electric motor such as that indicated at M which rotates the engine for starting purposes may be automatically switched off by the movement of the control lever H from the starting to the normal running position as shown.

The switch for the motor M conveniently "contact points H", H andthus closes the circuit of the motor M when the lever H is moved into its starting position and automatically opens this circuit when the lever H is moved into its normal running orhigh compression position.

In the alternative construction illustrated diagrammatically. in Figure 2 the sleeve N is operated by a lever 0 one end of which is restrained by a link or the like 0 while the other end engages an eccentric on a lay shaft P, an intermediate point in the lever engaging a spherical or other self aligning joint in the sleeve.

The la shaft P from which in the case of a muti-eylinder engine all the sleeves may be operated,.is driven from the engine crank shaft Q, through gearing comprising its shaft relatively to the skew gear Q and thus cause rotation of the skew gears Q and P and hence of the lay shaft independently of any rotation thereof due to the rotation of the crankshaft. Thus, in this arrangement, the actual change of relative positions takes place between the crankshaft and'the lay shaft and not between the lay shaft and the valves as in the construction illustrated in Figure 1.

In the construction illustrated in Figure 2 the lever R may be connected to a valve for permitting a gaseous combustible charge from a carburettor or the like to be delivered to the engine when starting and interconnections between other controls and the lever B may be provided in a similar manner to the interconnection of controls with the lever H described with reference to the construction shown in Figure l.

The axial movement of the lay shaft in the Figure 1 construction and the axial movement of the skew gear Q in the Figure 2 construction is conveniently so proportioned as to retard the sleeve valvetiming by about 90 in relation to the crank shaft angle when starting. Thus, if for high compression running the inlet port closes 30 after bottom dead centre giving a compression ratio of to 1, then, for starting, the inlet port will close 120 late, or about three-quarters of the way up the compression stroke, giving an effective compression ratio of about 4.5 to 1. \Vith this low effective compression ratio it is possible to rotate the engine either by hand or by means of a barring'engine or motor of moderate size. On reaching a suitable speed the lay shaft D or skew gear Q is moved axially into its v normal running position giving a full charge and the effective compression ratio necessary for the operation of the engine as' a compression ignition or Diesel type engine. Owing to the momentum of the flywheel the speed. of the engine can be maintained in spite of the high compression pressure and the liquid fuel injection can be brought into operation when the engine will run on its normal or compression ignition cycle.

The operation of an engine according to this invention is conveniently as follows For starting as a low compression engine employing a combustible charge the control lever H is placed in the starting position the fuel pumps being thereby cut off, the ignition switched on and the carburettor J 4 connected to the induction pipe J 2 as explained above. The engine is then turned over by hand or by the electric or other starting motor M and starts as a low compression engine employing a gaseous combustible charge. \Vhen a sufiicient speed has been attained the control lever H or R is thrown over into the normal running position which, as set forth above, preferably simul taneously moves the valve-operating mechanism to its normal high compression or running position, cuts off the supply of gaseous combustible mixture from the carburettor M and admits pure air to the induction pipe J", switches off the ignition current and admits liquid fuel to the fuel injection 'sprayers B thus enabling the engine to run as a high compression liquid injection unit in the ordinary manner.

\Vhen the invention is applied to a multicylinder internal combustion engine it may be found desirable in some cases to vary the timing of the valves or one or more of the cylinders only, the timing of the remaining valve or valves being maintained constant in relation to the crank shaft.

What I claim as my invention and desire motion to the sleeve, means for controlling I this mechanism so as to vary the timing of the sleeve in relation to the crank shaft whereby the charge compressed within the cylinder on each compression stroke can be reduced at starting, means for cutting off the liquid fuel supply, and an interconnection between the mechanism for varying the valve timing and that for cutting ofi' the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression.

2. In an internal combustion engine of the Diesel type the combination of. a cylinder having inlet and exhaust ports therein,

a sleeve valve disposed within the cylinder and adapted to control these ports, means for injecting a charge of liquid fuel into the cylinder, a crank shaft, mechanism actuated from the crank shaft for operating the sleeve valve, means for controlling this mechanism so as to vary the timing of the sleeve in relation to the crank shaft whereby the charge compressed within the cylinder on each compression stroke can be reduced at starting, means for cutting off the liquid fuel supply, and an interconnection between the mechanism for varying the valve timing and that for cutting off the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine .will operate at its normal running compression.

3. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, means for injecting a charge of liquid fuel into the cylinder, a sleeve valve disposed within the cylinder and adapted to control the ports therein, a crank shaft, mechanism actuated from the crank shaft for imparting a combined oscillating and reciprocating motion to the sleeve, means for controlling this mechanism so as to vary the timin of the sleeve in relation to the crank sliaft whereby the charge compressed within the cylinder on each compression stroke can be reduced at starting, means for cutting off the liquid fuel supply, an interconnection between the mechanism for varying the valve timing and that forcutting off the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression, means for supplyin an explosive gaseous mixture to the cylin er when the mechanism controlling the valve timing is in its reduced compression position, and means for igniting this gaseous mixture.

4.,In an internal combustion engine of the Diesel t pe the combination of alcylinder having inlet and exhaust ports therein, asleeve valve disposed within the cylinder and-adapted to control these ports, means for injecting a charge ofliquid fuel into the cylinder, a crank shaft, mechanism actuated from the crank shaft for operating the sleeve valve, means for controlling this mechanism so as to vary the timing, of the sleeve in relation to the crank shaft whereby the chargecompressed within the cylinder can be reduced at starting, means for cutting off the li uid fuel supply, an interconnection between t e mechanism for varying the valve timing and that for cutting off the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression, means for supplying an exp sive gaseous mixture to the cylinder when the mechanism controlling the valve timing is in its reduced compression position, and means for igniting this mixture.

5. In an internal combustion engine of the Diesel type the combination of at least one cylinder having inlet and exhaust ports therein, a sleeve valve disposed within each cylinder and adapted to control the ports, means for injecting a charge of liquid fuel into the cylinder, a short crankshaft adjacent to each sleeve, a crank pin on each short shaft, a flexible connection between the crank pin and the sleeve whereby rotation of the short shaft imparts a combined oscillating and reciprocating motion to the sleeve, a skew gear on each short shaft, a lay shaft, a second skew gear on the lay shaft meshing with the skew gear on the short shaft, an

engine crank shaft, an operative driving connection between the engine crank shaft and the lay shaft, means for moving the lay shaft in the direction of its length so as to vary the timing of each sleeve valve in relation to the-crank shaft whereby the charge compressed within the cylinder on each com pression stroke can be reduced, means for cutting off the liquid fuel supply, and an interconnection between the means formoving the lay shaft longitudinally and the means for cutting off the liquid fuelsupply so arran ed that fuel injection can only take place w en the valve timmg is such that .crank pin and the sleeve whereby rotation of the short shaft imparts a comblned oscillatmg and reciprocating motion to the 'sleeve, a skew (gear on each short shaft, a lay shaft, a secon skew gear on the lay shaft meshing with the skew gear on the short shaft, an

fuel,

engine crank shaft, an operative'driving connection between the engine crank shaft and the lay shaft, means for moving the lay shaft in the direction of its length so as to vary the timing of each sleeve-valve in relation to the crank shaft whereb the charge i compressed within the cylin er on )each compression stroke can be reduced, means.

for cutting off the liquid fuel supply, an interconnection between the'means or moving the lay shaft longitudinall means for cutting o-if the liquid uel supply so arranged that fuel injection can only take place when the valve timing is such that the engine Will operate at its normal Working compression, means for supplying a gaseous explosive charge to the cylinder when the valve timing is such as to reduce the maximum compression pressure, and means for igniting this gaseous charge.

7. In an internal combustion engine of the Diesel type the combination of a plurality of cylinders having inlet and exhaust ports therein, means for injecting liquid fuel into the cylinders, a sleeve valve disposed within gears on the lay shaft meshing respectively and the lit with the skew gears on the short crank shafts, an engine crank shaft, an operative driving. connection between the engine crank shaft and the lay shaft, means for moving the lay shaft longitudinallyso as to vary simultaneously the timing of all the sleeves in relation to the crank shaft whereby the' charge compressed within each cylinder on "its, compression stroke can be reduced at starting, meansfor cutting off the liquid fuel supplly, and an interconnection between the mec anism. for moving the lay shaft longitudinally and the means for cutting off the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal worln'ng compression.

8. In an internal combustion engine of the Diesel type the combination of a plurality the short crank shaft imparts a combined oscillating and reciprocating motion to the sleeve, a skew gear on each short shaft, an

engine crank shaft, a single lay shaft, skew gears on the lay shaft meshing respectively with the skew gears on the short crank shafts,'an engine crank shaft, an operative driving connection between the enginecrank shaft and the lay shaft, means for moving the lay shaft longitudinally so as to vary simultaneously the timing of all the sleeves in relation to the crank shaft whereby the charge compressed within each cylinder on its compression stroke can be reduced at starting, means for cutting off the hquid fuel supply, an interconnection between the mechanism for moving the lay shaft lon itudinally and the means for cutting off t e liquid fuel supply so arranged that fuel injections can only take place whenthe valvetiming is such that the engine will operate at its normal working compression, means for supplying an explosive gaseous mixture to the cylinders when the valve timing is such as to reduce the maximum compression pressure, and mean for igniting this mixture.

9. In an internal combustion englne of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, at least one valve controlling these orts, means for injecting a charge of liquid el into the cylinder, a crank shaft, mechanism actuated from the crank shaft for operating the valves, means for controlling this mechanism so as to vary the timing of the valves in relation to the crank shaft whereby the charge compressed within the cylinder on each compression stroke can be reduced when starting, means for cutting off the liquid fuel supply, an inter-connection between the means for varying the valve timing and means for cutting off the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression, means for supplying an explosive gaseous mixture to the cylinder when the maximum compression pressure is re duced, and means for igniting this mixture.

10. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust orts therein, a sleeve valve disposed within the cylinder and adapted to control the ports therein, a crank shaft, mechanism actuated from the crank shaft for imparting a combined oscillating and reciprocating motion to the sleeve, means for controlling this mechanism so as to vary the timing of the sleeve in relation to the crank shaft whereby the charge compresses within the cylinder on each com pression stroke can be reduced when starting the engine, a starting motor for rotating the crank shaft, a switch controlling this motor, and an interconnection between the switch and the mechanism for controlling the valve timing such that the starting motor is automatically switched off when this mechanism is moved into its full compression position.

11. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, means for injecting a' charge of liquid fuel into the cylinder, a sleeve valve disposed within the cylinder and adapted to control the ports therein, a crank shaft, mechanism actuated from the crank shaft for im arting a combined oscillating and reciprocating motion to the sleeve, means for controlling this mechanism so as to vary the timing of the sleeve in relation to the crank shaftwhereby the charge compressed within the cylinder on each compression stroke can be reduced at starting, means for cutting off the liquid fuel supply, an interconnection between the mechanism for varyin the valve timing and that for cutting off t e liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression, a starting motor for rotating the crank shaft, a switch controlling this motor and an inter-connection between the switch and the mechanism for controlling the valve timing such that the starting motor is automatically switched off. when this mechanism is moved into-its full compression position.

12. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, a sleeve valve disposed within the cylinder and adapted to control these ports, means for injecting a charge of liquid fuel into the cylinder, a crank shaft, mechanism actuated from the crank shaft for o crating the sleeve valve, means for control ing'this mechanism so as to vary the timing of the sleeve in relation to the crank shaft whereby the charge compressed within the cylinder on each compression stroke can be reduced at startin means for cutting off the liquid fuel supp y, an interconnection between the mechanism for vagying the valve timin and that for cutting o the liquid fuel supp y so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal'running compression, a starting motor for rotating the crank shaft, a switch controlling this motor, and an interconnection between the switch and the mechanism for controlling the valve timing such that the starting motor is automatically switched off when this mechanism is moved into its full compression position.

13. In an. internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, a sleeve valve disposed within the cylinder and adapted to control these ports, meansfor injecting a charge of liquid fuel into the cylinder, a crank shaft, mechanism actuated from the crank shaft for operatingthe sleeve valve, means for controlling this mechanism so as to' vary the timing of the sleeve in relation to the crank shaft whereby the charge compressed within the cylinder can be reducedat starting, means for cutting off the liquid fuel supply, an interconnection between the mechanism for varying the valve timing and that for cutting off the liquid .fuel supply so arranged that fuel injection can only take place when thevalve timing is such that the engine will operate at its normal running compression, means for supplying an explosive gaseous mixture to the cylinder when the mechanism controlling the valve timing is in its reduced compression position, means for igniting this mixture, a starting motor for rotating the crank shaft, a switch controlling this motor, and an interconnection between' the switch and the mechanism for controlling the valve timing such that the starting motor is automaticall switched off when this mechanism is move into its full compression position.

14. In an internal combustion engine of the Diesel type the combination of a plurality of cylindershaving inlet and exhaust ports therein, means for injecting liquid fuel into the cylinders, a sleeve valve disposed within each cylinder and adapted to control the ports therein, a short crank shaft adjacent to each sleeve, a crank pin on each short shaft, a flexible connection between the crank pin and the sleeve whereby rotation of the short crank shaft imparts a combined oscillating and reciprocating motion to the sleeve, a skew gear on each short shaft, an engine crank shaft, a single lay shaft, skew gears on the lay shaft meshing respectively with the skew gears on the short crank shafts, an engine crank shaft, an, operative driving connection between the engine crank shaft and the lay shaft, means for moving the lay shaft longitudinally so as to vary simultaneously the timing of all the sleeves in relationto the crank shaft wherebythe charge compressed within each cylinder on its compression stroke can he reduced at starting, means for cutting off the liquid fuel supply, an interconnection between the mechanism for moving the lay shaft longitudinally and the means for cutting off the liquid'fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal working compression, means for supplying an explosive gaseous mixture to the cylinders when the valve timing is such as to reduce the maximum compression pressure, means for igniting this mixture, a starting motor for rotating the crank shaft, a switch controlling this motor, and an interconnection between the switch and the mechanism for controlling the valve timing such that the starting motor is automatically switchedofi' when this mechanism is moved into its full compression position,

15. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, a sleeve valve disposed within the cylinder and adapted to control these ports, a crank shaft, mechanism actuated from the crank shaft for imparting combined oscillating and reciprocating motion to the sleeve, means for controlling this mechanism where? by part of the charge drawn into the cylinder on the induction stroke is forced out again at the beginning of the' compression stroke and the maximum compression pressure thus reduced, means for supplying an explosive gaseous mixture to the cylinder when the maximum compression pressure is thus reduced, means for igniting this gascutting off the supply of gaseous mixture to the cylinder when the mechanism controlling the valve timing is moved into its full compression position.

16. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, means for injecting a. charge of liquid fuel into the cylinder, a sleeve valve disposed within the cylinder and adapted to control the ports therein, accrank shaft, mechanism eousmixture and means for automatically actuated from the crank shaft for imparting a combined oscillating andreciprocatmg motion to the sleeve, means for controlling this mechanism so as to vary the timing of the sleeve in relation to the crank shaft whereby the charge compressed within the cylinder on each compression stroke can be reduced at starting, means for cutting off the liquid fuel supply, an interconnection between the mechanism for varying the valve timing and that for cutting off the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression, means for supplying an explosive gaseous mixture to the cylinder when the mechanism controlling the valve timing is in its reduced compression position, means for igniting this gaseous mixture, and means for automatically cutting oil the supply of gaseous mixture to the cylinder when the mechanism controlling the valve timing is moved into its full compression position.

' 17. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, a sleeve valve disposed within the cylinder and adapted to control these ports, means for injecting a charge of liquid fuel into the cylinder, a crank shaft, mechanism actuated from the crank shaft for operating the sleeve valve, means for controlling this mechanism so as to vary the timing of the sleeve in relation to the crank shaft whereby the charge compressed within the cylinder can be reduced at starting, means for cutting off the liquidfuel supply, an interconnection between the mechanism for varying the valve timing and that for cutting off the liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression, means for supplying an explosive gaseous mixture to the cylinder when the mechanism controlling the valve timing is in its reduced compression position, means for igniting this mixture, and means for automatically cutting off the supply ofgaseous mixture to the cylinder when the mechanism controlling the valve timing is moved into its full compression position.

18. In an internal combustion engine of the Diesel type the combination ofa cylin der having inlet and exhaust ports therein, at least one valve controlling these ports, a crank shaft, mechanism actuated from the crank shaft for operating the valves, means forcontrolling this mechanism so as to vary the timing of the valves in relation to the crank shaft whereby the charge compressed within the cylinder on each compression stroke can-be reduced when starting, means for supplying a gaseous explosive mixture to the cylinder when the mechanism controlling the valve timing is in its reduced compression position, means 'for igniting this mixture, and means for automatically cutting off the supply of gaseous mixture to the cylinder when the mechanism controlling the valve timing is moved into its full compression position.

19. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, at least one valve controlling these ports, means for injecting a charge of liquidfuel into the cylinder, a crank shaft, mechanism actuated from the crank shaft for operating the valves, means for controlling this mechanism so as to vary the timing of the valves in relation to the crank shaft whereby the charge compressed within the cylinder on each compression stroke can be reduced when starting, means for cutting off the liquid fuel supply, an interconnection between the means for varying the valve timing and the means for cutting off th'c liquid fuel supply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compre sion, means for supplying an explosive gaseous mixture to the cylinder when the maximum compression pressure is reduced, means for igniting this mixture, and means for automatically cutting oil the supply of gaseous mixture to the cylinder when the mechanism controlling the valve timing is moved into its full compression position.

20. In an internal combustion engine of the Diesel type the combination of a cylinder having inlet and exhaust ports therein, a sleeve valve disposed within the cylinder and adapted to control these ports, means for injecting a charge of liquid fuel into the cylinder, a crank shaft, mechanism actuated from the crank shaft for operating the sleeve valve, means for controlling this mechanism so as to vary thetiming of the sleeve in relation to the crank shaft whereby the charge compressed within the cylinder can be reduced at starting, means for cutting off the liquid fuel supply, an interconnection betweenthe mechanism for varying the valve timing and that for cutting off the liquid fuelsupply so arranged that fuel injection can only take place when the valve timing is such that the engine will operate at its normal running compression, means for supplyin an explosive gaseous mixture to the cylin er when the mechanism controlling the valve timing is in its reduced compression position, means for igniting this mixture, means for automatically cutting oil the supply of gaseous mixture to the cylinder when the mechanism controlling the valve timing ,is in its full compression position, a starting motor for rotating the crank shaft, a switch controlling this motor and an interconnection between this switeh and the mechanism controlling the valve timing such that the startin motor is automatically switched off when t is mechanism is moved into its full compression osition.

In testimony wliereof I have signed my name to this specification.

HARRY RALPH RICARDO. 

